ui, logic: design for license ui and forcing the user to enter a key on first open

This change integrates the license key ui into the application and makes it necessary for the user to enter a correct
key. The check for a correct key is done on startup and whenever a project is loaded. The check for the key also
includes a check whether the location of the application has changed.

bin/app/data/gui/setting_window/window.css

@@ -75,3 +75,13 @@ QLineEdit:disabled {
 	color: white;
 	background: #2D3F85;
 }
+
+#windowButton:disabled {
+	color: lightgray;
+}
+
+QToolTip {
+	background-color: <color:tool_tip/background>;
+	color: <color:tool_tip/text>;
+	font-size: <setting:font_size>pt;
+}